The appropriate data storage format for a telephone contact is not straightforward. While it might seem numeric, treating it as an integer or floating-point number is generally discouraged. A common example illustrates this: phone numbers often include leading zeros (e.g., in international formats) that would be truncated if stored numerically. Furthermore, arithmetic operations are rarely, if ever, performed on these identifiers, reinforcing the unsuitability of numerical formats.
Utilizing a character string offers several advantages. It preserves formatting conventions such as spaces, hyphens, and parentheses, which enhance readability. The string representation easily accommodates international dialing codes (e.g., +1, +44) and extensions. Historically, databases sometimes used fixed-length character fields, but modern systems favor variable-length strings to conserve storage space, particularly when dealing with large datasets of contacts. Furthermore, validating a string for a compliant pattern is typically simpler than ensuring numeric types match length or regional dialing plans.
